Alexander Nasonov <al...@yandex.ru> writes: > Brad Spencer wrote: >> Alexander Nasonov <al...@yandex.ru> writes: >> > Are there any downside of mixing legacy and non-legacy mountpoints? >> > E.g. if my /var is legacy but /var/crash is a normal ZFS mountpoint? >> >> That should work fine as long as /var was arranged to be mounted first. >> The other way around may and probably is trouble right now, where a >> zpool Not-legacy needs to be mounted so that a ZFS legacy filesystem or, >> in fact, any other filesystem type gets mounted under it. I believe >> that Solaris did and probably still does have this problem too. Legacy >> ZFS mounts should be perfectly workable even from single user when /usr >> isn't available yet for most simple use cases. > > Since I plan to migrate my ZFS setup to a smaller cgd disk, I gave > legacy mountpoints a try to see how much complexity they add. > > I have the following ZFS mountpoints in my setup > > /usr - legacy > /var - legacy > /var/log - legacy > /var/tmp - normal > /var/mail - normal > ... > > Ideally, I'd like to keep all datasets under one root: > > tank/base/usr - legacy > tank/base/var - legacy > tank/base/var/log - legacy > tank/base/var/mail - normal > > but it has a small inconvenience: every time I add a new dataset under > a legacy mountpoint (e.g. create a dataset for /var/spool), it can't > inherit a mountpoint from a legacy mountpoint and I have to set it > manually (zfs set mountpoint=/var/spool tank/base/var/spool).
Yes, that would very much be the case. Legacy mounts in ZFS are mostly there to make /etc/fstab (and simular ilk) work the same as one may be used to doing, so no inheritance. You do not have to use most of the zpool / zfs commands to get them mounted, but at the same time you can set their sizes and such. Getting too complicated with them, however, may introduce unexpected adventure. > One way to avoid this issue is to have separate hierarchies: > > tank/legacy > tank/legacy/usr > tank/legacy/var > tank/legacy/var/log > tank/base > tank/base/var > tank/base/var/mail > > but I'm pretty sure it has some downsides too. > > Alex -- Brad Spencer - b...@anduin.eldar.org - KC8VKS - http://anduin.eldar.org
